HOPKINTON – Machiko was ready to go the second she jumped out of the car.

"Ready to go to work? Ready to go to work?" Russ Doucette asked his 5-year-old Shepherd-Lab mix early Tuesday night.

Then stridently, he gave the order: "Find her."

The dog's mission: find a woman, "lost" in Hopkinton State Park during a mock rescue.

Doucette, 65, who lives in Framingham, has been a member of Massachusetts Canine Response Team, Inc., a statewide volunteer canine search and rescue organization since 2009. Machiko became a certified search dog in December 2011.

The dogs and their handlers look for children, hikers and hunters as well as Alzheimer's/dementia patients and despondent people. The teams work with state and local police and the state Department of Conservation and Recreation, which oversees state parks and reservations.

The number of times his organization goes out on searches has dropped due to the proliferation of cellphones, which authorities use to track down lost people.

Tuesday night's search was expected to be her last. Three weeks ago, she was diagnosed with an aggressive bone cancer. Her prognosis is not good – maybe six to nine months to live after a leg amputation and going through chemotherapy.

Doucette made the difficult decision to put down his canine pal.

"It is going to be the best thing for her," said Doucette, a retired real estate developer. "It will be hard for her not going to work everyday … quality of life is important and she wouldn't have had that."

Despite her limp, Machiko searched a snow-covered field Tuesday night and about 20 minutes later found Lyn Moraghan in some woods.

"Did you find someone?" Doucette asked. "Good job."

About 25 people turned out to watch her last mission and rewarded her with applause. Some of those folks gave her doggie treats after her fine work.

"She likes to work," Doucette said. "She gets super excited when I put my work clothes on and even more excited once her vest gets put on."

Machiko is an air-scenting dog, which means she sniffs for a generic human scent in the wind. These trained dogs use their noses to find the victim, then return to their handlers barking with the discovery, Doucette said.

Training the dogs takes hundreds of hours.

The dog's training includes agility and obedience, exposure to unfamiliar surroundings, and many mock search problems. Handlers develop map and compass, GPS and radio skills, according to the organization.

Machiko has taken part in many highly publicized searches, including a search for Leo Couto in Dracut in 2012. He was later found dead in the woods by another team.

Page 2 of 2 - In October, they were dispatched to North Conway, N.H., to help search for Abigail Hernandez, a 15-year-old who was last seen on Oct. 9. Machiko did not take part in the actual search, but was ready to help.

"We all form a bond to one another and the dogs," said Anson Demars, a team member from Charlton. He said he was thankful he could walk alongside Doucette during the search.

"Even though Mishi was in pain, she was very determined," Demars said.

Cheryl Oetting, one of the founding members of the group, was also on hand.

"It is really hard to lose a dog you've developed such a partnership with," she said. "The depth of the bond is hard to describe."

Three weeks ago, Machiko was taken to the veterinarian after she started limping during a training session.

"I thought it might be a pulled muscle and I took her to the vet," he said. "They took an X-ray and gave me a call saying it looked liked cancer. It turned out to be the most aggressive kind."

Doucette will say goodbye to Machiko at 11 this morning when she is euthanized. He teared up as he thanked everyone who helped organize the last search.

"I just wanted her to have her last hurrah," he said. "I know how much she loves working and I wanted to give her that chance."